Parameters Calibration of Time Domain Reflectometry(TDR) Based on Iterative Algorithm

The iterative thinking was used to calibrate the parameters of time domain reflectometry(TDR),in which the initial four parameters of Topp equation were determined by the water content observed by drying method and then four parameters were amended through the"fitting parameters-experimental calibration"procedure based on iterative algorithm.The results showed that:1The iterative process was an parameter optimization process for Topp model,which was demonstrated by that Akaike Information Criterion(AIC)decreased with the increase of the number of iterations,and correlation coefficient of model fitting increased gradually to 1;2Error of TDR decreased sharply with the increase of iteration numbers,which was 8.10% and 5.05% after the first and the second iteration respectively.